A polishing process may be performed on various parts in manufacture of automobiles, optical apparatuses or semiconductors. For example, a substrate for a hard disk, an optical lens or a silicon wafer may be polished.
A glass substrate, which is a part of a liquid crystal display (LCD), can be polished. When the glass substrate is used as a color filter substrate for an LCD or a substrate for a thin film transistor (TFT), it may need surface smoothness.
The glass substrate may be manufactured in two types: a fusion type and a floating type. In the floating type, the glass substrate may be manufactured by moving a horizontal roller with injecting a raw material melted in a melting furnace into it. Said glass substrate might need to be polished in a subsequent process in case of it might be wrinkled by the friction with the roller,